U.S. patent application number 12/182425 was filed with the patent office on 2009-08-06 for tools and methods for insertion and removal of medical implants.
Invention is credited to Christopher U. Phan.
Application Number | 20090198245 12/182425 |
Document ID | / |
Family ID | 42359517 |
Filed Date | 2009-08-06 |
United States Patent
Application |
20090198245 |
Kind Code |
A1 |
Phan; Christopher U. |
August 6, 2009 |
TOOLS AND METHODS FOR INSERTION AND REMOVAL OF MEDICAL IMPLANTS
Abstract
Medical devices and related methods for the treatment of spinal
conditions are described herein. In one embodiment, an apparatus
includes a first elongate member that defines a lumen and a second
elongate member that is movably disposed within the lumen of the
first elongate member. A distal end portion of the first elongate
member is configured to be releasably coupled to a spinal implant.
A distal end portion of the second elongate member includes a
driving member configured to engage an actuation member of the
spinal implant when the first elongate member is coupled to the
spinal implant. The driving member is configured to rotate the
actuation member to move the spinal implant between a collapsed
configuration and an expanded configuration. The first elongate
member configured to secure the spinal implant to the first
elongate member.
Inventors: |
Phan; Christopher U.; (San
Leandro, CA) |
Correspondence
Address: |
MEDTRONIC;Attn: Noreen Johnson - IP Legal Department
2600 Sofamor Danek Drive
Memphis
TN
38132
US
|
Family ID: |
42359517 |
Appl. No.: |
12/182425 |
Filed: |
July 30, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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61025991 |
Feb 4, 2008 |
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Current U.S.
Class: |
606/99 |
Current CPC
Class: |
A61F 2220/0025 20130101;
A61B 2017/0256 20130101; A61B 2090/061 20160201; A61F 2002/30556
20130101; A61F 2002/4658 20130101; A61B 17/7065 20130101; A61F
2002/30507 20130101; A61F 2/4611 20130101; A61F 2002/3055 20130101;
A61F 2/4455 20130101; A61F 2250/0009 20130101; A61F 2002/30579
20130101; A61F 2/4657 20130101; A61B 90/06 20160201 |
Class at
Publication: |
606/99 |
International
Class: |
A61B 17/58 20060101
A61B017/58 |
Claims
1. An apparatus, comprises: a first elongate member defining a
lumen; and a second elongate member movably disposed within the
lumen of the first elongate member; a distal end portion of the
first elongate member configured to be releasably coupled to a
spinal implant, a distal end portion of the second elongate member
including a driving member configured to engage an actuation member
of the spinal implant when the first elongate member is coupled to
the spinal implant, the driving member configured to rotate the
actuation member to move the spinal implant between a collapsed
configuration and an expanded configuration, the first elongate
member configured to secure the spinal implant to the first
elongate member.
2. The apparatus of claim 1, further comprising: a third elongate
member defining a lumen, the first elongate member being movably
disposed within the lumen of the third elongate member.
3. The apparatus of claim 1, further comprising: a third elongate
member defining a lumen, the first elongate member being movably
disposed within the lumen of the third elongate member, the third
elongate member configured to be matingly and removably coupled to
the spinal implant to prevent rotation of the spinal implant
relative to the third elongate member when coupled thereto.
4. The apparatus of claim 1, wherein the distal end portion of the
first elongate member includes a threaded portion configured to be
matingly coupled to a threaded portion on the spinal implant.
5. The apparatus of claim 1, wherein the distal end portion of the
first elongate member includes a quick connect fitting configured
to be matingly coupled to a corresponding quick connect portion of
the spinal implant.
6. The apparatus of claim 1, wherein the first elongate member is
formed at least partially with a flexible coil and the second
elongate member is bendable.
7. A method, comprising: coupling a distal end portion of a first
elongate member of an insertion tool to a first coupling portion on
a spinal implant such that the spinal implant is prevented from
longitudinal movement relative to the insertion tool; inserting a
distal end portion of a second elongate member of the insertion
tool into a second coupling portion of the spinal implant such that
the distal end portion of the insertion tool engages an actuator of
the spinal implant, the second elongate member being movably
disposed within a lumen of the first elongate member; after the
inserting, disposing the spinal implant into a selected location
within a patient's body; and rotating the second elongate member
relative to the first elongate member such that the actuator of the
spinal implant is rotated and moves the spinal implant from a
collapsed configuration to an expanded configuration.
8. The method of claim 7, further comprising: prior to the
inserting, coupling a distal end portion of a third elongate member
of the insertion tool to a third mating coupling portion of the
spinal implant such that the spinal implant is prevented from
rotating relative to the insertion tool while the third elongate
member of the insertion tool is coupled to the third mating
coupling portion of the spinal implant.
9. The method of claim 7, wherein the coupling and the inserting
are performed substantially simultaneously.
10. The method of claim 7, wherein the inserting includes inserting
at least a portion of a hexagon driver member of the second
elongate member through an opening defined by the second mating
coupling portion of the spinal implant.
11. The method of claim 7, wherein the inserting includes inserting
the spinal implant into a space between adjacent spinous
processes.
12. The method of claim 7, wherein the inserting includes inserting
the spinal implant into a space within an intervertebral disc.
13. The method of claim 7, further comprising: after the rotating,
moving the second elongate member within a lumen of a third
elongate member of the insertion tool to release the insertion tool
from the spinal implant.
14. An apparatus, comprising: a first elongate member defining a
lumen; a second elongate member movably disposed within the lumen
of the first elongate member; and a third elongate member, the
second elongate member being movably disposed within a lumen of the
third elongate member; the first elongate member including a first
coupling portion configured to be coupled to a spinal implant such
that the spinal implant is prevented from movement relative to the
first elongate member along a longitudinal axis defined by a distal
end portion of the first elongate member, the second elongate
member including a second coupling portion configured to be coupled
to the spinal implant, the second elongate member configured to
actuate the implant between a first configuration and a second
configuration when the second elongate member is rotated relative
to the first elongate member.
15. The apparatus of claim 14, wherein the second elongate member
is spring loaded such that the second coupling portion is biased
into an extended position relative to the distal end of the first
elongate member.
16. The apparatus of claim 14, wherein: the third elongate member
has a third coupling portion configured to be matingly coupled to a
corresponding coupling portion on the spinal implant, the third
coupling portion configured to prevent rotation of the spinal
implant relative to the third elongate member when coupled
thereto.
17. The apparatus of claim 14, wherein the first coupling portion
includes a threaded portion configured to be matingly coupled to a
threaded portion on the spinal implant.
18. The apparatus of claim 14, wherein the first coupling portion
includes a quick connect fitting configured to be matingly coupled
to a corresponding quick connect portion on the spinal implant.
19. The apparatus of claim 14, wherein the first elongate member
and the third elongate member are movable relative to each other
along the longitudinal axis between a first position in which the
first elongate member is coupled to the spinal implant, and a
second position in which the first elongate member is not coupled
to the spinal implant.
20. The apparatus of claim 14, wherein the second elongate member
has a centerline corresponding to the centerline of the first
elongate member, the apparatus further comprising: a first handle
coupled to a proximal end portion the first elongate member and
configured to rotate the first elongate member about the
longitudinal axis; and a second handle coupled to a proximal end
portion of the second elongate member and configured to rotate the
second elongate member about the longitudinal axis.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional
Application Ser. No. 61/025,991, entitled "Medical Implants and
Methods," filed Feb. 4, 2008, which is incorporated herein by
reference in its entirety.
[0002] This application is related to U.S. patent application
Attorney Docket Nos. KYPH-040/01US 305363-2273, entitled "Medical
Implants and Methods," KYPH-040/03US 305363-2270, entitled "Medical
Implants and Methods," and KYPH-040/04US 305363-2272, entitled
"Spine Distraction Tools and Methods of Use," each filed on same
date, the disclosures of each are hereby incorporated herein by
reference in their entirety.
BACKGROUND
[0003] The invention relates generally to the treatment of spinal
conditions, including, for example, the treatment of spinal
compression using percutaneous spinal implants for implantation
between adjacent spinous processes and/or percutaneous spinal
implants for implantation in a space associated with an
intervertebral disc.
[0004] Minimally-invasive procedures have been developed to provide
access to the space between adjacent spinous processes such that
major surgery is not required. Such known procedures, however, may
not be suitable in conditions where the spinous processes are
severely compressed. When the spinous processes are compressed, it
can be difficult to insert a spinal implant between adjacent
spinous processes. Moreover, such procedures can involve large or
multiple incisions. Further, some of the known implants configured
to be inserted into a space associated with an intervertebral disc
or between adjacent spinous processes may require actuation to an
expanded configuration after being inserted into the desired
position. Tools for providing such actuation can be difficult to
maneuver within the patient's body. Often, multiple tools are
required to insert and remove an implant and to actuate an implant
after being placed at a desired location.
[0005] Thus, a need exists for improvements in the methods and
tools used for the insertion and removal of spinal implants, such
as implants for implantation between adjacent spinous processes
and/or implants for implantation in a space associated with an
intervertebral disc. In addition, a need exists for improvements in
devices and methods for distracting anatomical structures to
provide access for an implant.
SUMMARY OF THE INVENTION
[0006] Medical devices and related methods for the treatment of
spinal conditions are described herein. In one embodiment, an
apparatus includes a first elongate member that defines a lumen and
a second elongate member that is movably disposed within the lumen
of the first elongate member. A distal end portion of the first
elongate member is configured to be releasably coupled to a spinal
implant. A distal end portion of the second elongate member
includes a driving member configured to engage an actuation member
of the spinal implant when the first elongate member is coupled to
the spinal implant. The driving member is configured to rotate the
actuation member to move the spinal implant between a collapsed
configuration and an expanded configuration. The first elongate
member configured to secure the spinal implant to the first
elongate member.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a schematic illustration of an insertion/removal
tool according to an embodiment, and an implant shown in a first
configuration.
[0008] FIGS. 2 and 3 are schematic illustrations of the
insertion/removal tool of FIG. 1 shown between a first spinous
process and a second spinous process, and the implant of FIG. 1
shown in a first configuration and a second configuration,
respectively.
[0009] FIGS. 4 and 5 are schematic illustrations of a dilation
device according to an embodiment shown in a first configuration
and a second configuration, respectively.
[0010] FIGS. 6 and 7 are perspective views of a dilation device
according to an embodiment shown in a first configuration and a
second configuration, respectively.
[0011] FIG. 8 is a side perspective view of the dilation head of
the dilation device shown in FIG. 7 in the first configuration.
[0012] FIG. 9 is a cross-sectional view of the dilation head shown
in FIG. 8 in the first configuration, taken along line X-X in FIG.
8.
[0013] FIG. 10 is a perspective view of the dilation head of the
dilation tool shown in FIG. 7 in the second configuration.
[0014] FIG. 11 is a cross-sectional view of the dilation head shown
in FIG. 10 in the second configuration.
[0015] FIG. 12 is a cross-sectional view of the dilation device
shown in FIG. 6 in the first configuration.
[0016] FIG. 13 is an enlarged cross-sectional view of the dilation
device shown in FIG. 12.
[0017] FIG. 14 is a side perspective view of the outer shaft of the
dilation device of FIG. 6.
[0018] FIG. 15 is a side perspective view of the handle of the
dilation device of FIG. 6.
[0019] FIG. 16 is a side perspective view of the drive shaft of the
dilation device of FIG. 6.
[0020] FIG. 17 is a side perspective view of the indicator of the
dilation device of FIG. 6.
[0021] FIG. 18 is a side perspective view of the lock tab of the
dilation device of FIG. 6.
[0022] FIG. 19 is a top perspective view of an implant according to
an embodiment, in a first configuration.
[0023] FIG. 20 is a side perspective view of the implant shown in
FIG. 19 in the first configuration.
[0024] FIG. 21 is a cross-sectional view of the implant shown in
FIGS. 19 and 20, taken along line X-X in FIG. 19.
[0025] FIG. 22 is a top perspective view of the implant shown in
FIG. 19 in a second configuration.
[0026] FIG. 23 is a side perspective view of the implant shown in
FIG. 19 in the second configuration.
[0027] FIG. 24 is a cross-sectional view of the implant shown in
FIGS. 23 and 24 in the second configuration.
[0028] FIGS. 25 and 26 are exploded views of the implant
illustrated in FIGS. 19-24.
[0029] FIG. 27 is a side perspective view of an insertion/removal
tool, according to an embodiment.
[0030] FIG. 28 is side cross-sectional view of the
insertion/removal device of FIG. 27.
[0031] FIG. 29 is a side perspective view of the outer shaft of the
insertion/removal tool of FIG. 27.
[0032] FIG. 30 is a side perspective view of the intermediate shaft
of the insertion/removal tool of FIG. 27.
[0033] FIG. 31 is a side perspective view of the inner shaft of the
insertion/removal tool of FIG. 27.
[0034] FIG. 32 is a distal perspective view of a portion of the
insertion/removal tool of FIG. 27.
[0035] FIG. 33 is an end perspective view of the implant of FIG.
19.
[0036] FIG. 34 is an exploded view of a portion of the
insertion/removal tool of FIG. 27.
[0037] FIG. 35 is a side perspective view of the release knob and
housing coupler of the insertion/removal tool of FIG. 27.
[0038] FIG. 36 is a perspective cross-sectional view of the release
knob and housing coupler of FIG. 35.
[0039] FIG. 37 is an exploded view of a portion of the
insertion/removal tool of FIG. 27.
[0040] FIG. 38 is a side perspective view of the actuation handle
and release knob coupler of the insertion/removal tool of FIG.
27.
[0041] FIG. 39 is a perspective cross-sectional view of the
actuation handle and release knob coupler of FIG. 38.
[0042] FIGS. 40 and 41 are perspective views of the
insertion/removal tool of FIG. 27 and the implant of FIG. 19 shown
in a first configuration and a second configuration,
respectively.
[0043] FIGS. 42 and 43 are perspective views of an
insertion/removal tool according to another embodiment of the
invention and an implant according to another embodiment shown in a
first configuration and a second configuration, respectively.
[0044] FIG. 44 is a side perspective view of an insertion/removal
device according to another embodiment and an implant according to
another embodiment.
[0045] FIG. 45 is a distal perspective view of the
insertion//removal tool of FIG. 44
[0046] FIG. 46 is a side cross-sectional view of a portion of the
insertion/removal tool of FIG. 44 and the implant of FIG. 44.
[0047] FIG. 47 is an end perspective view of the implant of FIG.
44.
[0048] FIG. 48 is a side cross-sectional view of a portion of the
insertion/removal tool of FIG. 44.
[0049] FIG. 49 is a side perspective view of a portion of the
insertion/removal tool of FIG. 44.
[0050] FIG. 50 is a side perspective view of a portion of the
intermediate shaft of the insertion/removal tool of FIG. 44.
[0051] FIG. 51 is a side perspective view of the outer shaft of the
insertion/removal tool of FIG. 44.
[0052] FIG. 52 is a side perspective view of the inner shaft of the
insertion/removal tool of FIG. 44.
[0053] FIG. 53 is a side perspective cross-sectional view of the
handle of the insertion/removal tool of FIG. 44.
[0054] FIG. 54 is a bottom perspective view of the release knob of
the insertion/removal tool of FIG. 44.
DETAILED DESCRIPTION
[0055] Devices and methods for performing medical procedures are
described herein. Dilation tools are described that can be used to
dilate or distract adjacent anatomical structures, such as adjacent
spinous process implants. Such devices can be also be configured to
provide an indication or measurement of the amount of distraction.
Also described herein are various implant insertion/removal tools
and implants. The insertion/removal tools can be used to insert
percutaneously an implant into, for example, a space between
adjacent spinous processes, or within an intervertebral disc space,
and then used to actuate the implant between a first configuration
(e.g., collapsed configuration) and a second configuration (e.g.,
expanded configuration). The insertion/removal tools can also be
used to reposition or remove an implant from the patient's body.
For example, an insertion/removal tool as described herein can be
inserted into the patient's body and coupled to the implant while
the implant is still implanted in the body.
[0056] In some embodiments, an apparatus includes a first elongate
member that defines a lumen and a second elongate member that is
movably disposed within the lumen of the first elongate member. A
distal end portion of the first elongate member is configured to be
releasably coupled to a spinal implant. A distal end portion of the
second elongate member includes a driving member configured to
engage an actuation member of the spinal implant when the first
elongate member is coupled to the spinal implant. The driving
member is configured to rotate the actuation member to move the
spinal implant between a collapsed configuration and an expanded
configuration. The first elongate member configured to secure the
spinal implant to the first elongate member.
[0057] In some embodiments, a method includes coupling a distal end
portion of a first elongate member of an insertion tool to a first
coupling portion on a spinal implant such that the spinal implant
is prevented from longitudinal movement relative to the insertion
tool. A distal end portion of a second elongate member of the
insertion tool is inserted into a second coupling portion of the
spinal implant such that the distal end portion of the insertion
tool engages an actuator of the spinal implant. The second elongate
member is movably disposed within a lumen of the first elongate
member. The spinal implant is then disposed into a selected
location within a patient's body. The second elongate member is
then rotated relative to the first elongate member such that the
actuator of the spinal implant is rotated and moves the spinal
implant from a collapsed configuration to an expanded
configuration.
[0058] In some embodiments, an apparatus includes a first elongate
member that defines a lumen and a second elongate member that is
movably disposed within the lumen of the first elongate member. The
second elongate member is movably disposed within a lumen of a
third elongate member. The first elongate member includes a first
coupling portion configured to be coupled to a spinal implant such
that the spinal implant is prevented from movement relative to the
first elongate member along a longitudinal axis defined by a distal
end portion of the first elongate member. The second elongate
member includes a second coupling portion configured to be coupled
to the spinal implant. The second elongate member is configured to
actuate the implant between a first configuration and a second
configuration when the second elongate member is rotated relative
to the first elongate member.
[0059] In one embodiment, an apparatus includes a measurement tool
coupled to a distal end portion of an elongate member. A size of
the measurement tool is configured to change by a first amount when
the measurement tool is moved between a first configuration and a
second configuration. An actuator is coupled to a proximal end
portion of the elongate member and is configured to rotate about an
axis substantially parallel to at least a portion of a center line
of the elongate member to move the measurement tool between the
first and the second configurations. A size indicator is disposed
at a proximal end portion of the elongate member that is configured
to move axially relative to the elongate member by a second amount
when the measurement tool is moved between the first and second
configurations.
[0060] In another embodiment, an apparatus includes an elongate
member having a center line that is non-linear. The elongate member
has a first shaft and a second shaft and at least a portion of the
second shaft is movably disposed within first shaft. A measurement
tool is coupled to a distal end portion of the elongate member. A
size of the measurement tool is configured to change when the
measurement tool is moved between a first configuration and a
second configuration. An actuator is configured to rotate the
second shaft relative to the first shaft to move the measurement
tool between the first configuration and the second configuration.
A size indicator is configured to indicate the change in the size
of the measurement tool when the measurement tool is moved between
the first configuration and the second configuration. In some
embodiments, an apparatus includes a measurement tool coupled to a
distal end portion of an elongate member. A size of the measurement
tool is configured to change when the measurement tool is moved
between a first configuration and a second configuration. The
measurement tool includes a spacer having a first spacer member and
a second spacer member. The first spacer member is configured to
move relative to the second spacer member when the measurement tool
is moved between the first configuration and the second
configuration. The measurement tool also has a distal actuator that
has a first actuator surface that is matingly and movably coupled
to the first spacer member, and a second actuator surface that is
matingly and movably coupled to the second spacer member. A
proximal actuator is coupled to a proximal end portion of the
elongate member and is configured to rotate about an axis
substantially parallel to at least a portion of a center line of
the elongate member to move the distal actuator. The distal
actuator is configured to move the first spacer member relative to
the second spacer.
[0061] As used in this specification and the appended claims, the
singular forms "a," "an" and "the" include plural referents unless
the context clearly dictates otherwise. Thus, for example, the term
"a member" is intended to mean a single member or a combination of
members, "a material" is intended to mean one or more materials, or
a combination thereof. Furthermore, the words "proximal" and
"distal" refer to direction closer to and away from, respectively,
an operator (e.g., surgeon, physician, nurse, technician, etc.) who
would insert the medical device into the patient, with the tip-end
(i.e., distal end) of the device inserted inside a patient's body
first. Thus, for example, the implant end first inserted inside the
patient's body would be the distal end of the implant, while the
implant end to last enter the patient's body would be the proximal
end of the implant.
[0062] The term "parallel" is used herein to describe a
relationship between two geometric constructions (e.g., two lines,
two planes, a line and a plane, two curved surfaces, a line and a
curved surface or the like) in which the two geometric
constructions are substantially non-intersecting as they extend
substantially to infinity. For example, as used herein, a line is
said to be parallel to a curved surface when the line and the
curved surface do not intersect as they extend to infinity.
Similarly, when a planar surface (i.e., a two-dimensional surface)
is said to be parallel to a line, every point along the line is
spaced apart from the nearest portion of the surface by a
substantially equal distance. Two geometric constructions are
described herein as being "parallel" or "substantially parallel" to
each other when they are nominally parallel to each other, such as
for example, when they are parallel to each other within a
tolerance. Such tolerances can include, for example, manufacturing
tolerances, measurement tolerances or the like.
[0063] The term "normal" is used herein to describe a relationship
between two geometric constructions (e.g., two lines, two planes, a
line and a plane, two curved surfaces, a line and a curved surface
or the like) in which the two geometric constructions intersect at
an angle of approximately 90 degrees within at least one plane. For
example, as used herein, a line is said to be normal to a curved
surface when the line and an axis tangent to the curved surface
intersect at an angle of approximately 90 degrees within a plane.
Two geometric constructions are described herein as being "normal"
or "substantially normal" to each other when they are nominally
normal to each other, such as for example, when they are normal to
each other within a tolerance. Such tolerances can include, for
example, manufacturing tolerances, measurement tolerances or the
like.
[0064] It should be understood that the references to geometric
constructions are for purposes of discussion and illustration. The
actual structures may differ from geometric ideal due to tolerances
and/or other minor deviations from the geometric ideal.
[0065] FIG. 1 is a schematic illustration of an insertion/removal
tool 700 according to an embodiment of the invention coupled to a
spinal implant 720. The insertion/removal tool 700 can include an
inner shaft 750 movably disposed within a lumen (not shown) of an
intermediate shaft 730, and an outer shaft 710. Although not in
cross-section, for illustration purposes, FIG. 1 is a schematic
representation of the intermediate shaft 730 and the inner shaft
750 that would otherwise not be visible through the outer shaft
710. The intermediate shaft 730 is movably disposed within a lumen
(not shown in FIG. 1) of the outer shaft 710. A proximal end
portion 711 of the outer shaft 710 is coupled to a housing 785. A
proximal end portion 731 of the intermediate shaft 730 is coupled
to a release knob 790 and a proximal end portion 751 of the inner
shaft is coupled to a handle 780.
[0066] The inner shaft 750, intermediate shaft 730 and outer shaft
710 share a common longitudinal axis A-A. The release knob 790 can
be rotated to actuate movement of the intermediate shaft 730, and
the handle 780 can be rotated independent of the release knob 790
to actuate movement of the inner shaft 750.
[0067] A distal end portion 721 of the outer shaft 710 can include
a coupling portion configured to be coupled to, or engage an
implant engagement member 722 of an implant 720 as described in
more detail below with reference to specific embodiments. For
example, in some embodiments, the distal end portion 721 of the
outer shaft 710 defines an opening configured to receive an
external implant engagement member of the spinal implant.
Alternatively, the implant engagement member 722 can have an
opening that can receive a portion of the insertion/removal tool
700. In some embodiments, the outer shaft 710 when coupled to the
spinal implant can prevent the spinal implant from rotating
relative to the insertion/removal tool 700.
[0068] A distal end portion 741 of the intermediate shaft 730 can
include a coupling portion configured to be coupled to a mating
coupling portion of the spinal implant 720. In some embodiments,
the distal end portion 741 of the intermediate shaft 730 includes a
threaded portion (not shown in FIG. 1) configured to be threadedly
coupled to a corresponding threaded portion on the spinal implant
720. In some embodiments, the distal end portion 741 of the
intermediate shaft 730 includes a quick connect feature configured
to be releasably coupled to a corresponding quick connect feature
on the spinal implant 720. The intermediate shaft 730 when coupled
to the spinal implant 720 can prevent the spinal implant 720 from
moving longitudinally relative to the insertion/removal tool
700.
[0069] A distal end portion 761 of the inner shaft 750 can be
coupled to the spinal implant 720 and used to actuate the spinal
implant 720 between a collapsed configuration and an expanded
configuration. For example, the distal end portion 761 of the inner
shaft 750 can include a drive portion or member (not shown in FIG.
1) configured to engage a head of a threaded actuating member or
drive screw (not shown in FIG. 1) of the spinal implant 720. The
drive member can be, for example, a hexagon-shaped protrusion
configured to be received within a hexagon-shaped opening of
threaded actuating member. The inner shaft 750 can be, for example,
spring loaded at its proximal end portion 751 such that the distal
end portion 761 is biased distally to ensure the drive member fits
tightly into the head of a drive screw (as described in more detail
below) of a spinal implant.
[0070] The insertion/removal tool 700 can be used to insert the
spinal implant 720 into a desired location within a patient's body
and actuate the spinal implant 720 between a collapsed
configuration and an expanded configuration. For example, the
insertion/removal tool 700 can be coupled to the spinal implant 720
by securing the intermediate shaft 730 to the implant engagement
member 722 of spinal implant 720 (as described in more detail
below) and coupling the drive member of the inner shaft 750 to the
actuating member (drive screw) of the spinal implant 720. With the
spinal implant 720 in a collapsed configuration, the
insertion/removal tool 700 can then be used to insert
percutaneously the spinal implant 720 into a space between adjacent
spinous processes S1 and S2 as shown schematically in FIG. 2.
[0071] Once positioned at a desired location, the inner shaft 750
can be actuated by rotating the handle 780 independently from the
release knob 790 and the housing 785, which in turn causes the
actuating member (e.g., drive screw) of the spinal implant 720 to
rotate and moves the spinal implant 720 from the collapsed
configuration to an expanded configuration as shown in FIG. 3. In
this example, the spinal implant 720 when in the expanded
configuration is configured to limit lateral movement of the spinal
implant 720 when positioned between the adjacent spinous processes
S1 and S2. In some embodiments, the spinal implant 720 can be
configured to limit extension of the adjacent spinous processes,
while allowing for flexion. In other embodiments, the
insertion/removal tool 700 can be used to insert and actuate other
types of implants, such as for example, an implant configured to be
disposed within an intervertebral disc space. Such implants are
described in U.S. patent application Attorney Docket No.
KYPH-040/01US 305363-2277, which is incorporated herein by
reference in its entirety.
[0072] After the spinal implant 720 has been expanded and is secure
within a desired location, the intermediate shaft 730 can be
decoupled from the implant engagement portion 722 of the implant
720 via rotation of the release knob 790. The implant
insertion/removal tool 700 can then be removed from the body while
leaving the spinal implant 720 in position within the body of a
patient.
[0073] The implant insertion/removal tool 700 can also be used to
remove and/or reposition an implant already disposed within the
body of a patient. For example, the insertion/removal tool 700 can
be coupled to the spinal implant 720 while the spinal implant 720
is disposed within the patient's body in the same manner as
described above. The spinal implant 720 can then be moved to its
collapsed configuration by rotating the actuation handle 780 of the
insertion/removal tool 700 in an opposite direction such that the
drive member rotates the actuating member of the spinal implant 720
and moves the spinal implant 720 to the collapsed configuration.
With the spinal implant 720 secured to the insertion/removal tool
700, the insertion/removal tool 700 can be used to move or
reposition the spinal implant 720 within the patient's body, or
remove the spinal implant 720 from the patient's body.
[0074] FIGS. 4 and 5 are each a schematic illustration of a
dilation device (also referred to herein as a "distraction device")
according to an embodiment. A dilation device 800 can be used to
distract adjacent anatomical structures, such as adjacent spinous
processes. The distraction device 800 can also be used to dilate or
distract tissue within a patient's body. In some embodiments, a
dilation device 800 can be used to measure a distance between
adjacent anatomical structures.
[0075] The dilation device 800 can include a dilation head 810, an
outer shaft 860, a drive shaft 870 (shown in FIG. 5) movably
disposed within a lumen (not shown in FIG. 4) of the outer shaft
860, a lock tab 880, a handle 886 and an indicator 890. The
dilation head 810 has a distal end portion 820, a proximal end
portion 830 and a central portion 840. The dilation head 810 also
defines a lumen (not shown in FIG. 4).
[0076] The central portion 840 includes a first dilation member 841
and a second dilation member 851. The first dilation member 841 and
the second dilation member 851 are each configured to be moved
between a first configuration as shown in FIG. 4 and a second
configuration as shown in FIG. 5. For example, the drive shaft 870
is coupled to the distal end portion 820 of the dilation head 810
and is used to move the distal end portion 820 and the proximal end
portion 830 to and from each other as described in more detail
below with reference to a specific embodiment.
[0077] The central portion 840 of the dilation head 810 can also
include one or more markers 848 that be used to position the
dilation head 810 at a desired location within a patient's body.
For example, the markers 848 can be radiotranslucent holes that are
viewable on a fluoroscope.
[0078] The handle 886 of the dilation tool 800 is coupled to the
drive shaft 870 and to the indicator 890. The handle 886 of the
dilation tool 800 is configured to rotate the drive shaft 870 of
the dilation tool 1300 when in the second configuration. The lock
tab 880 of the dilation tool 800 is configured to engage the outer
shaft 860 (described in more detail below) to prevent the handle
886 from rotating with respect to the outer shaft 860. The
indicator 890 of the dilation tool 800 can be used to determine the
amount of dilation produced by expanding the first dilation member
841 and the second dilation member 851. For example, the indicator
890 can move axially along the outer shaft 860, and the amount of
axial movement traveled by the indicator 890 can correspond to the
amount of distraction made by the dilation device 800.
[0079] In use, dilation head 810 of the dilation tool 800 while in
the first configuration (FIG. 4) is inserted percutaneously between
adjacent anatomical structures, such as in a space between a pair
of adjacent spinous processes. The distal end portion 820 of the
dilation head 810 is inserted first and is moved until the central
portion 840 is positioned between the anatomical structures. Once
in a desired location, the dilation tool 800 can be moved from the
first configuration (FIG. 4) to the second configuration (FIG. 5).
As the dilation tool 800 is moved to the second configuration, the
first dilation member 841 and the second dilation member 851
contact the adjacent anatomical structures and exert a force to
dilate or distract the adjacent anatomical structures. The amount
of distraction can be observed on the indicator 890. After
distracting the anatomical structures a desired amount, the
dilation tool 800 can be moved back to the first configuration
(FIG. 4) to remove the dilation tool 800 from the patient's
body.
[0080] FIGS. 6-18 illustrate a dilation tool 1300 according to an
embodiment. Dilation tool 1300 includes a dilation head 1310 and an
actuation portion 1305 (FIGS. 6 and 7) including an outer shaft
1360, a drive shaft 1370 (see FIGS. 12 and 13), a lock tab 1380, a
handle 1386 and an indicator 1390. FIG. 6 illustrates the dilation
tool 1300 with the dilation head 1310 in a first configuration
(e.g., unexpanded or collapsed) and with the lock tab 1380 secured
to the outer shaft 1360, preventing the handle 1386 from moving
relative to the outer shaft 1360. FIG. 7 illustrates the dilation
tool 1300 with the dilation head 1310 in a second configuration
(e.g. expanded) with the lock tab 1380 removed and the indicator
1390 slid partially outside of the handle 1386.
[0081] The dilation head 1310 of dilation tool 1300 has a distal
end portion 1320, a proximal end portion 1330 and a central portion
1340. Various components of dilation head 1310 are matingly and
movably coupled together, for example, by mating protrusions and
grooves of the type shown and described in U.S. patent application
Attorney Docket No. KYPH-040/03US, which is incorporated herein by
reference in its entirety. The central portion 1340 is coupled
between the distal end portion 1320 and the proximal end portion
1330. The dilation head 1310 also defines a lumen 1315 (see FIG. 9)
that is defined collectively by the proximal end portion 1330, the
central portion 1340 and the distal end portion 1320. The lumen
1315 is configured to allow a proximal end portion 3172 of the
drive shaft 3170 to pass through the first dilation head 1310 when
the dilation head 1310 is in the first configuration.
[0082] As shown in FIGS. 8-11, the distal end portion 1320 of
dilation head 1310 includes a tapered surface 1322, a first
engagement surface 1326, a second engagement surface 1327, a first
protrusion 1328 and a second protrusion 1329. The distal end
portion 1320 of dilation head 1310 also defines a threaded portion
1324 (see FIG. 9) that is configured to threadedly engage a
threaded portion 1378 of a distal end portion 1376 of the drive
shaft 1370 as described below. The threaded portion 1324 has a
predetermined length such that the longitudinal travel of the drive
shaft 1370 within the threaded portion is limited. Similarly
stated, the threaded portion 1324 is a "blind hole" to limit the
longitudinal distance that the drive shaft 1370 can move relative
to the distal end portion 1320 of the dilation head 1310. In this
manner, the amount of distraction and/or measurement by the tool
1300 can be limited.
[0083] The first engagement surface 1326 of the distal end portion
1320 is angularly offset from a longitudinal axis A.sub.L defined
by the dilation head 1310 by an angle between 0 degrees and 90
degrees. Similarly, the second engagement surface 1327 of the
distal end portion 1320 is angularly offset from the longitudinal
axis A.sub.L by an angle between 0 degrees and 90 degrees. Although
the angle of the first engagement surface 1326 is shown as being
equal, but in an opposite direction to the angle of the second
engagement surface 1327 (e.g., the angle of the first engagement
surface is +110 degrees and the angle of the second engagement
surface 1327 is -110 degrees), in other embodiments, the angle of
the first engagement surface 1326 and the angle of the second
engagement surface 1327 can be different. As described in more
detail herein, the angular offset of the first engagement surface
1326 and the angular offset of the second engagement surface 1327
are associated with moving the dilation head 1310 between a first
configuration (FIGS. 6, 8 and 9) and a second configuration (FIGS.
7, 10 and 11).
[0084] The first protrusion 1328 of the distal end portion 1320 has
an undercut such that the first dilation member 1341 of the central
portion 1340 of the dilation head 1310 can be slidably coupled to
the distal end portion 1320 of the dilation head 1310. Similarly,
the second protrusion 1329 of the distal end portion 1320 has an
undercut such that the second dilation member 1351 of the central
portion 1340 can be slidably coupled to the distal end portion
1320. More particularly, the first protrusion 1328 and second
protrusion 1329 each have a trapezoidal cross-sectional shape. In
some embodiments, for example, the first protrusion 1328 and second
protrusion 1329 can each have a dovetail protrusion.
[0085] The proximal end portion 1330 of dilation head 1310 includes
a tool engagement member 1332, a first engagement surface 1336, a
second engagement surface 1337, a first protrusion 1338 and a
second protrusion 1339. The first engagement surface 1336 of the
proximal end portion 1330 is angularly offset from the longitudinal
axis A.sub.L of the dilation head 1310 by an angle between 0
degrees and 90 degrees. Similarly, the second engagement surface
1337 of the proximal end portion 1330 is angularly offset from the
longitudinal axis A.sub.L by an angle between 0 degrees and 90
degrees. Although the angle of the first engagement surface 1336 is
shown as being equal, but in an opposite direction to the angle of
the second engagement surface 1337 (e.g., the angle of the first
engagement surface 1336 is +110 degrees and the angle of the second
engagement surface 1337 is -110 degrees), in other embodiments, the
angle of the first engagement surface 1336 and the angle of the
second engagement surface 1337 can be different. As described in
more detail herein, the angular offset of the first engagement
surface 1336 and the angular offset of the second engagement
surface 1337 are associated with moving the dilation head 1310
between a first configuration (FIGS. 6, 8 and 9) and a second
configuration (FIGS. 7, 10 and 11).
[0086] The first protrusion 1338 of the proximal end portion 1330
has an undercut such that the first dilation member 1341 of the
central portion 1340 of the dilation head 1310 can be slidably
coupled to the proximal end portion 1330 of the dilation head 1310.
Similarly, the second protrusion 1339 of the proximal end portion
1330 has an undercut such that the second dilation member 1351 of
the central portion 1340 can be slidably coupled to the proximal
end portion 1330. More particularly, the first protrusion 1338 and
second protrusion 1339 each have a trapezoidal cross-sectional
shape. In some embodiments, the first protrusion 1338 and second
protrusion 1339 can each have a dovetail protrusion.
[0087] The central portion 1340 of dilation head 1310 includes a
first dilation member 1341 and a second dilation member 1351. The
first dilation member 1341 includes a proximal engagement surface
1342 and a distal engagement surface 1343. The central portion 1340
of the dilation head 1310 can also include radiotranslucent holes
1348 that are viewable on an imaging device (e.g., a fluoroscope).
The radiotranslucent holes 1348 can be used as markers to help
position the dilation head 1310 with relative to the spinous
processes. The first dilation member 1341 defines a notch 1346 (see
FIG. 11) configured to allow the drive shaft 1370 to pass through
the first dilation member 1341.
[0088] The distal engagement surface 1343 of the first dilation
member 1341 defines a plane that is angularly offset from the
longitudinal axis A.sub.L of the dilation head 1310 by an angle
between 90 degrees and 180 degrees. Moreover, the angular offset of
the distal engagement surface 1343 of the first dilation member
1341 is supplementary with the angular offset of the first
engagement surface 1326 of the distal end portion 1320 (i.e., the
angles sum to 180 degrees). Similarly stated, the distal engagement
surface 1343 is substantially parallel to the first engagement
surface 1326 of the distal end portion 1320. Accordingly, the first
dilation member 1341 is slidably disposed against the distal end
portion 1320.
[0089] The distal engagement surface 1343 of the first dilation
member 1341 defines a distal groove 1345 having a trapezoidal
cross-sectional shape. In this embodiment, the distal groove 1345
has a dovetail shape that corresponds to the shape of the first
protrusion 1328 of the distal end portion 1320. The distal groove
1345 is configured to receive and to slide along the first
protrusion 1328 of the distal end portion 1320. The undercut of the
first protrusion 1328 of the distal end portion 1320 slidably
maintains the first protrusion 1328 of the distal end portion 1320
within the distal groove 1345. The distal groove 1345 of the distal
engagement surface 1343 and the protrusion 1328 of the distal end
portion 1320 collectively allow movement of the first dilation
member 1341, with respect to the distal end portion 1320, in a
direction substantially parallel to the proximal engagement surface
1342 of the first dilation member 1341. Moreover, the distal groove
1345 of the distal engagement surface 1343 and the protrusion 1328
of the distal end portion 1320 collectively limit movement of the
first dilation member 1341 with respect to the distal end portion
1320, in a direction substantially normal to the proximal
engagement surface 1342 of the first dilation member 1341. The
distal engagement surface 1343 of the first dilation member 1341
contacts and is configured to slide along the first engagement
surface 1326 of the distal end portion 1320 when the distal groove
1345 slides along the first protrusion 1328 of the distal end
portion 1320.
[0090] The proximal engagement surface 1342 of the first dilation
member 1341 defines a plane that is angularly offset from the
longitudinal axis A.sub.L of the dilation head 1310 by an angle
greater than 90 degrees. Moreover, the angular offset of the
proximal engagement surface 1342 of the first dilation member 1341
is supplementary with the angular offset of the first engagement
surface 1336 of the proximal end portion 1330. For example, the
proximal engagement surface 1342 is substantially parallel to the
proximal engagement surface 1342 of the proximal end portion 1330.
Accordingly, the first dilation member 1341 is slidably disposed
against the proximal end portion 1330.
[0091] The proximal engagement surface 1342 of the first dilation
member 1341 defines a proximal groove 1344 having a trapezoidal
cross-sectional shape. In this embodiment, the proximal groove 1344
has a dovetail shape that corresponds to the shape of the first
protrusion 1338 of the proximal end portion 1330. The proximal
groove 1344 is configured to receive and to slide along the first
protrusion 1338 of the proximal end portion 1330. The undercut of
the first protrusion 1338 of the proximal end portion 1330 slidably
maintains the first protrusion 1336 of the proximal end portion
1330 within the proximal groove 1344. The proximal groove 1344 of
the proximal engagement surface 1342 and the protrusion 1338 of the
proximal end portion 1330 collectively allow movement of the first
dilation member 1341, with respect to the proximal end portion
1330, in a direction substantially parallel to the distal
engagement surface 1343 of the first dilation member 1341.
Moreover, the proximal groove 1344 of the proximal engagement
surface 1344 and the protrusion 1338 of the proximal end portion
1330 collectively limit movement of the first dilation member 1341
with respect to the proximal end portion 1330, in a direction
substantially normal to the distal engagement surface 1343 of the
first dilation member 1341. The proximal engagement surface 1342 of
the first dilation member 1341 contacts and is configured to slide
along the first engagement surface 1336 of the proximal end portion
1330 when the proximal groove 1344 slides along the first
protrusion 1336 of the proximal end portion 1330.
[0092] Likewise, the second dilation member 1351 of the central
portion 1340 includes a proximal engagement surface 1352 and a
distal engagement surface 1353. The second dilation member 1351
defines a notch 1356 (see FIG. 10) configured to allow the drive
shaft 1370 to pass through the first dilation member 1341. The
proximal engagement surface 1352 defines a proximal groove 1354 and
the distal engagement surface 1353 defines a distal groove 1355.
The second dilation member 1351 is configured similar to the first
dilation member 1341 and is therefore not described in detail
herein.
[0093] FIGS. 12 and 13 are each a cross-sectional view of the
dilation tool 1300 (with the dilation head 1310 in the first
configuration) to illustrate the connection between the dilation
head 1310 and the actuation portion of the dilation tool 1310. The
various components of the actuation portion of the dilation tool
1300 are shown individually in FIGS. 14-18. The outer shaft 1360 of
the dilation tool 1300 is shown in FIG. 14. The outer shaft 1360
includes a proximal end portion 1362 and a distal end portion 1366.
The proximal end portion 1362 of the outer shaft 1360 includes a
threaded portion 1363 configured to be coupled to a threaded
portion 1373 of the indicator 1390 described in more detail below.
At least a portion of the outer shaft 1360 can be formed with a
flexible material such that it can bend and/or assume a curved
shape. In other embodiments, however, the outer shaft 1360 can be
substantially rigid, and can be formed to include a curved shape as
desired. In some embodiments, the outer shaft 1360 can be formed at
least in part with a flexible coil. Multiple markers 1364 are
disposed on an outer surface of the outer shaft 1360 (see e.g.,
FIGS. 6 and 14). Distal end portion 1366 of the outer shaft 1360 is
configured to be coupled to the tool engagement member 1332 of the
distal end portion 1320 of the dilator head 1310. The outer shaft
1360 of the dilation tool 1300 defines a lumen 1361 (see FIG. 13)
configured to allow the drive shaft 1370 of the dilation tool to be
disposed within.
[0094] The drive shaft 1370 of the dilation tool 1300 is shown in
FIG. 16. The drive shaft 1370 of the dilation tool 1300 includes a
proximal end portion 1372 and a distal end portion 1376. The drive
shaft 1370 of the dilation tool 1300 is configured to be disposed
within the lumen 1361 defined by the outer shaft 1360 of the
dilation tool 1300. The inner shaft 1370 can be formed at least in
part with a flexible material. For example, at least a portion of
the inner shaft 1370 can be formed with a coil. This allows the
inner shaft 1370 to be actuatable while disposed within the outer
shaft 1360, for example, when the outer shaft 1360 is curved. The
proximal end portion 1372 is disposed within a lumen 1387 defined
by the handle 1386 (see FIG. 15) of the dilation tool 1300 and is
coupled to the handle 1386 of the dilation tool 1300. A retaining
member 1377 is disposed at the distal end portion 1376 of the drive
shaft 1370 (see FIG. 13) and a retaining member 1375 is disposed at
the proximal end portion 1372 of the drive shaft 1370 to prevent
axial movement of the drive shaft 1370 relative to the outer shaft
1360. The retaining members 1377 and 1375 can be any suitable
structure configured to limit the axial movement of the drive shaft
1370 relative to the outer shaft 1360, such as, for example, a snap
ring, an E-ring, C-clip, a set screw, a detent configured to be
retained within a recess, and/or the like. A threaded portion 1378
of the distal end portion 1376 of the drive shaft 1370 is
configured to engage the threaded portion 1324 of the distal end
portion 1320 of the dilation head 1310.
[0095] The lock tab 1380 of the dilation tool 1300 is shown in FIG.
18. The lock tab 1380 of the dilation tool 1300 defines a notch
1381 configured to engage a cut-out portion 1383 of the outer shaft
1360 of the dilation tool 1300 as shown in FIGS. 6, 12 and 13. When
engaged with the outer shaft 1360, the lock tab 1380 is disposed
against the indicator 1390 of the dilation tool 1300, which
prevents the indicator 1390 and the handle 1386 from rotating with
respect to the outer shaft 1360.
[0096] The handle 1386 of the dilation tool 1300 is shown in FIG.
15. The handle 1386 defines a lumen 1387 configured to receive an
elongate portion 1393 (see FIG. 17) of the indicator 1390 of the
dilation tool 1300 as shown in FIGS. 12, 13 and 17. The elongate
portion 1393 is keyed into the lumen 1387 such that the handle 1386
and the indicator 1390 do not rotate relative to each other, but
the indicator 1390 can move axially relative to the handle 1386.
The handle 1386 is configured to rotate the drive shaft 1370
relative to the outer shaft 1360 to move the dilation head 1310
between the first configuration and the second configuration. In
some embodiment, the handle 1386 can rotate about a portion of a
centerline of the outer shaft 1360. For example, if the outer shaft
1360 is non-linear or curved, the outer shaft 1360 will have a
non-linear centerline and the handle 1386 can rotate about a
portion of the outer shaft 1360 that has a substantially linear
centerline.
[0097] The indicator 1390 of the dilation tool 1300 is shown in
FIG. 17. The indicator 1390 of the dilation tool 1300 defines a
lumen 1391 that extends through the elongate portion 1393 and
through a distal end portion 1394 of the indicator 1390. The
proximal end portion 1362 of the outer shaft 1360 is received
through an opening 1395 (see FIG. 13) defined by the distal end
portion 1394 of the indicator 1390 and the threaded portion 1363 of
the outer shaft 1360 matingly engages the a threaded portion 1373
defined within the lumen 1391 of the indicator 1390.
[0098] The indicator 1390 is used to provide an indication to the
user of the amount or size of dilation or distraction that has been
produced by the tool 1300. As the handle 1386 of the dilation tool
1300 is rotated, the indicator 1390 will rotate relative to the
outer shaft 1360 and is drawn longitudinally along the threaded
portion 1363 of the outer shaft 1360. The distance that the
indicator 1390 has moved longitudinally can correspond to the
amount of distraction produced and/or the size of the cavity being
measured. For example, when used to distract adjacent spinous
processes, a location of the indicator 1390 relative to the markers
1364 on the outer shaft 1360 can indicate the distance the
indicator 1390 has moved and the corresponding distance between
and/or amount of distraction of the adjacent spinous processes.
Similarly, when used to measure the space between adjacent spinous
processes and/or between vertebral end plates, a location of the
indicator 1390 relative to the markers 1364 on the outer shaft 1360
can indicate the distance the indicator 1390 has moved and the
corresponding distance between the adjacent spinous processes
and/or the vertebral end plates. In some embodiments, the markers
1364 can include numerical measurements of the amount of
distraction and/or size of the space being measured. In other
embodiments, the markers 1364 can correspond to different spacers
that can be disposed within the space based on the amount of
distraction and/or size of the space being measured Similarly
stated, in some embodiments, the markers 1364 can include
qualitative indications (e.g., part numbers, spacer designations or
the like) associated with the amount of distraction and/or size of
the space being measured.
[0099] The threaded portion 1373 of the indicator 1390 can have the
same pitch as the threaded portion 1378 of the distal end portion
1376 of the drive shaft 1370 such that the distance the distal end
portion 1376 travels within the distal head 1310 correlates to the
distance the indicator 1390 travels along the outer shaft 1360. In
some embodiments, the pitch of the threaded portion 1373 is
different than the pitch of the threaded portion 1378 to change the
correlation to the indicator 1390.
[0100] In use, with the dilation head 1310 in the first
configuration and the lock tab 1380 engaged with the outer shaft
1360 (see e.g., FIG. 6), the dilation tool 1300 is inserted
percutaneously to a location within a patient's body. For example,
the dilation tool 1300 can be disposed within a space between a
pair of adjacent spinous processes. The distal end portion 1320 of
the dilation head 1310 is inserted first and is moved until the
central portion 1340 of the dilation head 1310 is positioned in the
space between the adjacent spinous processes.
[0101] Once between the spinous processes, the dilation tool 1300
can be moved from the first configuration to the second
configuration (see e.g., FIG. 7). This is accomplished by removing
the lock tab 1380 from the outer shaft 1360 and rotating the handle
1386. Rotation of the handle 1386 causes the drive shaft 1370 to
rotate, which in turn causes the distal end portion 1320 of the
dilation head 1310 to move toward the proximal end portion 1330 of
the dilation head 1310. The distal end portion 1320 of the dilation
head 1310, and the proximal end portion 1330 of the dilation head
1310 exert a force on the first dilation member 1341 of the central
portion 1340 of the dilation head 1310 and on the second dilation
member 1351 of the central portion 1340 of the dilation head
1310.
[0102] The force causes the first dilation member 1341 of the
central portion 1340 of the dilation head 1310 to move in the
direction AA as shown in FIG. 8 with respect to the distal end
portion 1320 of the dilation head 1310 and the proximal end portion
1330 of the dilation head 1310. Likewise, the force causes the
second dilation member 1351 of the central portion 1340 of the
dilation head 1310 to move in the direction BB as shown in FIG. 8
with respect to the distal end portion 1320 of the dilation head
1310 and the proximal end portion 1330 of the dilation head 1310.
The force exerted by the first dilation member 1341 and the second
dilation member 1351 on the adjacent spinous processes, causes the
spinous processes to distract.
[0103] As the handle 1386 of the dilation tool 1300 is rotated, the
indicator 1390 of the dilation tool 1300 rotates and moves
longitudinally with respect to the outer shaft 1360 of the dilation
tool 1300 as described above. The movement of the indicator 1390
corresponds to a distance between the adjacent spinous processes,
at least a portion of which also corresponds to the amount of
distraction produced between the adjacent spinous processes. When a
desired amount of distraction has been achieved, the dilation tool
1300 can be moved back to the first configuration and removed from
the patient's body. To do this, the handle 1386 of the dilation
tool 1300 can be rotated in an opposite direction causing the
dilation tool 1300 to return to the first configuration.
[0104] In some embodiments, the handle 1386 of the dilation tool
1300 can include a torque limiting mechanism (not shown) to prevent
over-distraction of a particular space. For example, in some
embodiments the dilation tool 1300 can be used to create a void
within a disc space and/or repair a bone fracture. A torque
limiting mechanism can allow the user to apply a force to the bone
structure up to a predetermined maximum value. In this manner, the
dilation tool 1300 can prevent over-distraction during use.
[0105] Although the dilation tool 1300 is shown is being movable
between a first configuration (FIG. 8) and a second configuration
(FIG. 10), the dilation tool 1300 can be maintained in any number
of different configurations. For example, the dilation tool 1300
can be maintained in any suitable configuration between the first
configuration and the second configuration. Said another way, the
dilation tool 1300 can be placed in an infinite number of different
configurations between the first configuration and the second
configuration. Thus, the space between the spinous processes can be
distracted by the first dilation member 1341 and the second
dilation member 1351 by any desired amount within a predetermined
range. In this manner, a single dilation tool 1300 can be used
within a wide range locations within the body requiring different
amounts of distraction and/or measurement.
[0106] Moreover, this arrangement allows the amount of distraction
and/or measurement to be varied in situ over time. For example, in
some embodiments, the amount of distraction and/or measurement can
be varied within a range of approximately 8 mm to 16 mm. Within
this range, the size of the central portion 1340 can be adjusted to
any desired amount by rotating the handle 1386 a predetermined
amount, as described above. In other embodiments, the range of
distraction and/or measurement can be approximately 4 mm (e.g., a
range from 5 mm to 9 mm, a range from 12 mm to 16 mm, or the like).
In yet other embodiments, the range of distraction and/or
measurement can be approximately 3 mm (e.g., a range from 10 mm to
13 mm, a range from 12 mm to 15 mm, or the like).
[0107] FIGS. 27-41 illustrate an implant insertion/removal tool
1400, according to another embodiment of the invention. To better
illustrate the function and use of the implant insertion/removal
tool 1400, an example implant is described with reference to FIGS.
19-26.
[0108] FIGS. 19-26 illustrate an implant 2100, according to an
embodiment. Implant 2100 includes a distal end portion 2110, a
central portion 2140 and a proximal end portion 2180. At least a
portion of the central portion 2140 is disposed in a space between
the distal end portion 2110 and the proximal end portion 2180. The
implant 2100 defines a lumen 2146 (see e.g., FIGS. 25 and 26) and
includes a drive screw 2183 disposed within the lumen 2146. Drive
screw 2183 has a tool head 2184 configured to mate with and/or
receive a tool for rotating the drive screw 2183, as further
described below.
[0109] The distal end portion 2110 of implant 2100 includes an
actuator 2111 and a distal retention member 2120. Actuator 2111
includes a tapered surface 2112, a threaded portion 2114 (see FIG.
21), and an engagement surface 2116. The threaded portion 2114 is
disposed fixedly within the lumen 2146 and is configured to receive
the drive screw 2183, as described above. The engagement surface
2116 of the actuator 2111 is angularly offset from the longitudinal
axis A.sub.L of the implant 2100 by an angle between 0 degrees and
90 degrees. As described in more detail herein, the angular offset
of the engagement surface 2116 is associated with moving the
implant 2100 between a first configuration (FIG. 19) and a second
configuration (FIG. 22). The engagement surface 2116 includes a
protrusion 2118 having an undercut such that the distal retention
member 2120 can be coupled to the actuator 2111. More particularly,
the protrusion 2118 has a trapezoidal cross-sectional shape. In
some embodiments, the protrusion 2118 is a dovetail protrusion.
[0110] Distal retention member 2120 includes an outer surface 2121,
a first engagement surface 2122, and a second engagement surface
2123 opposite the first engagement surface 2122. The distal
retention member 2120 defines a notch 2128 (see FIG. 24) configured
to allow the drive screw 2183 to pass through the distal retention
member 2120 when the implant 2100 is in the first configuration.
The first engagement surface 2122 of the distal retention member
2120 defines a plane that is angularly offset from the longitudinal
axis A.sub.L of the implant 2100 by an angle between 90 degrees and
180 degrees. Moreover, the first engagement surface 2122 of the
distal retention member 2120 is substantially parallel to the
engagement surface 2116 of the actuator 2111. Accordingly, the
distal retention member 2120 is slidably disposed against actuator
2111.
[0111] The first engagement surface 2122 of the distal retention
member 2120 defines a first groove 2124 having a trapezoidal
cross-sectional shape. In this embodiment, the first groove 2124
has a dovetail shape that corresponds to the shape of the
protrusion 2118 of the actuator 2111. The first groove 2124 of the
first engagement surface 2122 and the protrusion 2118 of the
actuator 2111 collectively allow movement of the distal retention
member 2120, with respect to the actuator 2111, in a direction
substantially parallel to the second engagement surface 2123 of the
distal retention member 2120. Moreover, the first groove 2124 of
the first engagement surface 2122 and the protrusion 2118 of the
actuator 2111 collectively limit movement of the distal retention
member 2120, with respect to the actuator 2111, in a direction
substantially normal to the second engagement surface 2123 of the
distal retention member 2120. The first engagement surface 2122 of
the distal retention member 2120 contacts and is configured to
slide along the engagement surface 2116 of the actuator 2111 when
the first groove 2124 slides along the protrusion 2118 of the
actuator 2111.
[0112] The second engagement surface 2123 of the distal retention
member 2120 is substantially parallel to the distal engagement
surface 2143 of the central portion 2140 and defines a plane
substantially normal to the longitudinal axis A.sub.L of the
implant 2100. The second engagement surface 2123 of the distal
retention member 2120 defines a second groove 2126 having a
trapezoidal cross-sectional shape. In this embodiment, the second
groove 2126 has a dovetail shape that corresponds to the shape of
the distal protrusion 2145 of the central portion 2140. The second
groove 2126 of the second engagement surface 2123 and the distal
protrusion 2145 of the central body 2140 collectively limit
movement of the distal retention member 2120, with respect to the
central portion 2140, in a direction substantially normal to the
second engagement surface 2123 of the distal retention member 2120.
The second engagement surface 2123 of the distal retention member
2120 is slidably disposed against and/or coupled to the central
portion 2140 of the implant 2100, as described in more detail
herein.
[0113] Proximal end portion 2180 of implant 2100 includes a tool
engagement member 2182 and a proximal retention member 2160. Tool
engagement member 2182 is configured to mate with and/or receive an
insertion tool. Tool engagement member 2182 includes an engagement
surface 2186 and a hex portion 2185. The hex portion 2185 includes
a hexagonal shaped outer surface configured to be matingly received
within a portion of an insertion tool. In this manner, the hex
portion 2185 of the tool engagement member 2182 can limit
rotational motion of the implant 2100 about the longitudinal axis
A.sub.L, when the implant 2100 is coupled to an insertion tool. In
some embodiments, the hexagonal shaped outer surface of the hex
portion 2185 can be configured to facilitate the docking of the
insertion tool (not shown) onto the hex portion 2185 of the implant
2100. For example, in some embodiments, the outer surface of the
hex portion 2185 can include a lead-in chamfer, a tapered portion
and/or a beveled edge to facilitate the docking of the insertion
tool onto the hex portion 2185 of the implant 2100.
[0114] The hex portion 2185 defines a threaded portion 2190. The
threaded portion 2190 is configured to mate with and/or receive a
corresponding threaded portion of an insertion tool. In this
manner, the threaded portion 2190 can limit axial movement of the
implant 2100, with respect to the insertion tool, when the implant
2100 is inserted into a body of a patient, as described in further
detail below. Moreover, when the shaft 1430 of the insertion tool
is coupled within the threaded portion 2190, movement of the drive
screw 2183 along the longitudinal axis relative to the tool
engagement member 2182 is limited. In this manner, the coupling of
an insertion tool 1400 within the threaded portion 2190 can prevent
the drive screw 2183 from moving, thereby maintaining the implant
2100 in the first configuration. In other embodiments, the threaded
portion 2190 can include a retainer (e.g., a snap ring, an E-ring
or the like) to prevent translation of the drive screw 2183
relative to the tool engagement member 2182.
[0115] The engagement surface 2186 of the tool engagement member
2182 is angularly offset from the longitudinal axis A.sub.L of the
implant 2100 by an angle between 0 degrees and 90 degrees. The
engagement surface 2186 includes a protrusion 2188 having an
undercut such that the proximal retention member 2160 can be
coupled to the tool engagement member 2182. More particularly, the
protrusion 2188 has a trapezoidal cross-sectional shape. In this
embodiment, the protrusion 2188 is a dovetail protrusion.
[0116] Proximal retention member 2160 includes an outer surface
2161, a first engagement surface 2162, and a second engagement
surface 2163 opposite the first engagement surface 2162. The
proximal retention member 2160 defines a notch 2168 (see FIG. 26)
configured to allow the drive screw 2183 to pass through the
proximal retention member 2160 when the implant 2100 is in the
first configuration. The first engagement surface 2162 of the
proximal retention member 2160 defines a plane that is angularly
offset from the longitudinal axis A.sub.L of the implant 2160 by an
angle between 90 degrees and 180 degrees. Moreover, the first
engagement surface 2162 of the proximal retention member 2160 is
substantially parallel to the engagement surface 2186 of the tool
engagement member 2182. Accordingly, the proximal retention member
2160 is slidably disposed against the tool engagement member
2182.
[0117] The first engagement surface 2162 of the proximal retention
member 2160 defines a first groove 2164 having a trapezoidal
cross-sectional shape. In this embodiment, the first groove 2164
has a dovetail shape that corresponds to the shape of the
protrusion 2188 of the tool engagement member 2182. The undercut of
the protrusion 2188 of the tool engagement member 2182 slidably
maintains the protrusion 2188 of the tool engagement member 2182
within the first groove 2164. More particularly, the first groove
2164 of the first engagement surface 2162 and the protrusion 2188
of the tool engagement member 2182 collectively allow movement of
the proximal retention member 2160, with respect to the tool
engagement member 2182, in a direction substantially parallel to
the second engagement surface 2163 of the proximal retention member
2160. Moreover, the first groove 2164 of the first engagement
surface 2162 and the protrusion 2188 of the tool engagement member
2182 collectively limit movement of the proximal retention member
2160, with respect to the tool engagement member 2182, in a
direction substantially normal to the second engagement surface
2163 of the proximal retention member 2160. The first engagement
surface 2162 of the proximal retention member 2160 contacts and is
configured to slide along the engagement surface 2186 of the tool
engagement member 2182 when the first groove 2164 of the proximal
retention member 2160 slides along the protrusion 2188 of the tool
engagement member 2182.
[0118] The second engagement surface 2163 of the proximal retention
member 2160 is substantially parallel to the proximal engagement
surface 2142 of the central portion 2140 and defines a plane
substantially normal to the longitudinal axis A.sub.L of the
implant 2100. The second engagement surface 2163 of the proximal
retention member 2160 defines a second groove 2166 having a
trapezoidal cross-sectional shape. In this embodiment, the second
groove 2166 has a dovetail shape that corresponds to the shape of
the proximal protrusion 2144 of the central portion 2140. The
second groove 2166 of the second engagement surface 2163 and the
proximal protrusion 2144 of the central portion 2140 collectively
limit movement of the proximal retention member 2160, with respect
to the central body 2140, in a direction substantially normal to
the second engagement surface 2163 of the proximal retention member
2160. The second engagement surface 2163 of the proximal retention
member 2160 is slidably disposed against and/or coupled to the
central portion 2140 of the implant 2100, as described in more
detail herein.
[0119] The central portion 2140 of implant 2100 includes a proximal
engagement surface 2142, a distal engagement surface 2143, a
proximal protrusion 2144, a distal protrusion 2145 and an outer
surface 2141. The distal retention member 2120 is slidably coupled
to the central portion 2140. The second groove 2126 of the distal
retention member 2120 is configured to slidingly receive the distal
protrusion 2145 of the central portion 2140. The distal protrusion
2145 of the central portion 2140 has a dovetail shape slidably
maintaining it within the second groove 2126 of the distal
retention member 2120. The second engagement surface 2123 of the
distal retention member 2120 contacts and is configured to slide
along the distal engagement surface 2143 of the central portion
2140 when the second groove 2126 of the distal retention member
2120 slides along the distal protrusion 2145 of the central portion
2140.
[0120] Similarly, the proximal retention member 2160 is slidably
coupled to the central portion 2140. The second groove 2166 of the
proximal retention member 2160 is configured to slidingly receive
the proximal protrusion 2144 of the central portion 2140. The
proximal protrusion 2144 of the central portion 2140 has a dovetail
shape slidably maintaining it within the second groove 2166 of the
proximal retention member 2160. The second engagement surface 2163
of the proximal retention member 2160 contacts and is configured to
slide along the proximal engagement surface 2142 of the central
portion 2140 when the second groove 2166 of the proximal retention
member 2160 slides along the proximal protrusion 2144 of the
central portion 2140.
[0121] The implant 2100 has a first configuration (FIG. 19) and a
second configuration (FIG. 23). When the implant 2100 is in the
first configuration, the proximal end portion 2180, the distal end
portion 2110 and the central portion 2140 are substantially coaxial
(i.e., substantially share a common longitudinal axis). As
described above, the implant 2100 can be moved between the first
configuration and the second configuration by rotating the drive
screw 2183. When the drive screw 2183 is rotated as indicated by
the arrow CC in FIG. 20, the drive screw 2183 moves the actuator
2111 and the tool engagement member 2182 toward the central portion
2140. The engagement surface 2116 of the actuator 2111 exerts an
axial force on the first engagement surface 2122 of the distal
retention member 2120. Because the engagement surface 2116 of the
actuator 2111 is at an acute angle with respect to the longitudinal
axis A.sub.L, a component of the axial force transmitted via the
engagement surface 2116 to the first engagement surface 2122 of the
distal retention member 2120 has a direction as shown by the arrow
AA in FIG. 23. Said another way, a component of the force exerted
by the actuator 2111 on the distal retention member 2120 has a
direction that is substantially normal to the longitudinal axis
A.sub.L. This force causes the distal retention member 2120 to
slide on the engagement surface 2116 of the actuator 2111 causing
the distal retention member 2120 to move in the direction AA and
into the second configuration. Once the distal retention member
2120 slides on the engagement surface 2116 of the actuator 2111 a
predetermined distance, a portion of the engagement surface 2116 of
the actuator 2111 contacts a portion of the distal engagement
surface 2143 of the central portion 2140 preventing the distal
retention member 2120 from sliding further.
[0122] Similarly, when the drive screw 2183 is rotated as indicated
by the arrow CC in FIG. 20, the engagement surface 2186 of the tool
engagement member 2182 exerts an axial force on the first
engagement surface 2162 of the proximal retention member 2160.
Because the engagement surface 2186 of the tool engagement member
2182 is at an acute angle with respect to the longitudinal axis
A.sub.L, a component of the axial force transmitted via the
engagement surface 2186 to the first engagement surface 2162 of the
proximal retention member 2160 has a direction as shown by the
arrow AA in FIG. 23. Said another way, a component of the force
exerted by the tool engagement member 2182 on the proximal
retention member 2160 has a direction that is substantially normal
to the longitudinal axis A.sub.L. This force causes the proximal
retention member 2160 to slide on the engagement surface 2186 of
the tool engagement member 2182 causing the proximal retention
member 2160 to move in the direction AA and into the second
configuration. Once the proximal retention member 2160 slides on
the engagement surface 2186 of the tool engagement member 2180 a
predetermined distance, a portion of the engagement surface 2186 of
the tool engagement member 2180 contacts the proximal engagement
surface 2142 of the central portion 2140 preventing the proximal
retention member 2160 from sliding further. When the implant 2100
is in the second configuration the distal retention member 2120
and/or the proximal retention member 2160 are offset from the
central portion 2140 in a direction substantially normal to the
longitudinal axis A.sub.L.
[0123] The insertion tools described below can include an actuator
configured to be inserted into the tool head 2184 of the drive
screw 2183 to rotate the drive screw 2183 about the longitudinal
axis A.sub.L. This arrangement allows the drive screw 2183 to be
rotated without rotating the other portions of the implant 2100.
Accordingly, the implant 2100 can be inserted into, repositioned
within and/or removed from a body, as described above.
[0124] Referring now to FIGS. 27-41, the implant insertion/removal
tool 1400 is described in reference to being coupled to the implant
2100 described above. It should be understood that the
insertion/removal tool 1400 can be used to insert/remove and/or
actuate other types of implants. FIG. 27 is a perspective view of
the implant insertion/removal tool 1400 and FIG. 28 is a
cross-sectional view of the implant insertion/removal tool 1400
(also referred to herein as "insertion/removal tool"). As shown in
FIGS. 27 and 28 the implant insertion/removal tool 1400 includes an
outer shaft 1410, an intermediate shaft 1430, an inner shaft 1450,
an actuation handle 1480, a housing 1485 and a release knob
1490.
[0125] The actuation handle 1480 is coupled to the inner shaft
1450. The housing 1485 is coupled to the outer shaft 1410, and the
release knob 1490 is coupled to the intermediate shaft 1430. The
actuation handle 1480, the housing 1485 and the release knob 1490
share a common centerline or longitudinal axis. The actuation
handle 1480 can rotate about the longitudinal axis to rotate the
inner shaft 1450 independent of the release knob 1490 and the
intermediate shaft 1430. The release knob 1490 can rotate about the
longitudinal axis to rotate the intermediate shaft 1430 independent
of the handle 1480 and the inner shaft 1450.
[0126] As shown in FIG. 29, the outer shaft 1410 of the implant
insertion/removal tool 1400 includes a proximal end portion 1411
and a distal end portion 1421 (see also FIG. 27). Outer shaft 1410
of the implant insertion/removal tool 1400 defines a lumen (not
shown) configured to receive intermediate shaft 1430 of the implant
insertion/removal tool 1400. As best shown in FIG. 32, the distal
end portion 1421 of the outer shaft 1410 has an implant engagement
member 1422 configured to receive the external tool head of an
implant such as the external tool head 2185 of the implant 2100
described above and shown in FIG. 33. In this embodiment, the
implant engagement member 1422 is hexagon shaped, but other shapes
and configuration can alternatively be used.
[0127] Intermediate shaft 1430 of the implant insertion/removal
tool 1400 includes a proximal end portion 1431 and a distal end
portion 1441 (see e.g., FIG. 30). Intermediate shaft 1430 also
defines a lumen (not shown) configured to receive the inner shaft
1450 of the implant insertion/removal tool 1400. Distal end portion
1441 of the intermediate shaft 1430 has a threaded portion 1442
configured to be threadedly coupled to the inner surface of the
external tool head of an implant such as the inner surface of the
external tool head 2185 of the implant 2100.
[0128] As shown in FIGS. 28 and 34-36, the proximal end portion
1431 of the intermediate shaft 1430 is configured to be received in
a keyway 1436 of an elongate portion 1435 of the release knob 1490.
As best shown in FIGS. 34-36, a housing coupler 1432 is coupled to
the elongate portion 1435 of the release knob 1490 and a retainer
1434, such as an E-ring, retains the housing coupler 1432 on the
release knob 1490, while still allowing independent rotational
movement between the housing coupler 1432 and the release knob
1490. The elongate portion 1435 is disposed through a proximal end
1443 of the housing 1485. The threads on the housing coupler 1432
are threaded into a threaded portion 1483 (see FIG. 28) within the
lumen 1437 of the housing 1485. A central spring 1425 is coupled to
the proximal end portion 1431 of the intermediate shaft 1430 to
bias the intermediate shaft 1430 distally.
[0129] Inner shaft 1450 of the implant insertion/removal tool 1400
includes a proximal end portion 1451 and a distal end portion 1461
(see e.g., FIG. 31). The distal end portion 1461 of the inner shaft
1450 has a drive member 1462 configured to engage the tool head of
the drive screw of an implant such as the tool head 2184 of the
drive screw 2183 of the implant 2100. The inner shaft 1450 extends
through the intermediate shaft 1430, through the release knob 1490,
and the proximal end portion 1451 of the inner shaft 1450 is
coupled to the actuation handle 1480.
[0130] As shown in FIG. 28, the handle 1480 is coupled to a
proximal end of the release knob 1490. As shown in FIGS. 37-39, a
release knob coupler 1452 couples to a post 1454, and a retainer
1453 is disposed on an end of the post 1454. The retainer 1453 can
be, for example, an E-ring configured to retain the release knob
coupler 1452 on the post 1454 while still allowing independent
movement between the release knob 1490 and the handle 1480 (see
FIG. 38). The release knob coupler 1452 is threaded into a threaded
portion 1493 of the release knob 1490. The post 1454 defines a
keyway 1457 configured to receive the distal end portion 1451 of
the inner shaft 1450. A drive spring 1427 (see FIG. 28) is coupled
to the proximal end portion 1451 of the inner shaft 1450 to bias
the inner shaft 1450 into an extended position in which a distal
end of the driver member 1462 extends distally of the intermediate
shaft 1430 and the outer shaft 1410. This ensures that the drive
member 1462 fits tightly into the tool head (e.g., tool head 2184)
of the drive screw (e.g., drive screw 2183).
[0131] The implant insertion/removal tool 1400, can be used to
percutaneously insert an implant (e.g., implant 2100) into a space
in a body such as between adjacent spinous processes or within an
intervertebral disc space. The insertion/removal tool 1400 is first
coupled to the implant 2100 while the implant 2100 is in a first
configuration (e.g., collapsed configuration). The drive member
1462 is inserted through the tool engagement member 2182 (see FIG.
33) such that the drive member 1462 engages the tool head 2184 of
the drive screw 2183 and the hexagon-shaped portion of the implant
engagement member 1422 engages the hex portion 2185 of the implant
2100. The release knob 1490 is rotated, which rotates the
intermediate shaft 1430, and in turn threadedly couples the
threaded portion 1442 of the intermediate shaft 1430 to the
threaded portion 2190 of the implant 2100.
[0132] With the insertion/removal tool 1400 attached to the implant
2100, the tool engagement member 2182 prevents the implant 2100
from rotating relative to the insertion/removal tool 1400. In
addition, the threaded coupling of the intermediate shaft 1430 to
the implant 2100 prevents the implant from moving longitudinally
relative to the tool 1400 and also prevents the drive screw 2183
from moving longitudinally. Moreover, as described above when the
shaft 1430 of the insertion tool is coupled within the threaded
portion 2190 of the implant 2100, movement of the drive screw 2183
along the longitudinal axis relative to the tool engagement member
2182 is limited (i.e., the screw 2183 cannot "back out"). FIG. 40
illustrates the implant 2100 in the first configuration (e.g.,
collapsed configuration) coupled to the insertion/removal tool
1400.
[0133] The insertion/removal tool 1400 can then be used to insert
percutaneously the implant into a desired location within a
patient's body, such as in a space between adjacent spinous
processes. For example, a medical practitioner can insert the
implant 2100 percutaneously through a cannula into a body of a
patient. Once the implant is in the desired position, the actuation
handle 1480 can be rotated as indicated by the arrow CC in FIG. 40
independent of the housing 1485 and the release knob 1490. This in
turn rotates the inner shaft 1450 of the insertion/removal tool
1400 and the drive member 1462 of the distal end portion 1461 of
the inner shaft 1450. Rotation of the drive member 1462 in turn
rotates the drive screw 2184 of the implant 2100 and moves the
implant 2100 into a second configuration (e.g., expanded
configuration) as shown in FIG. 41.
[0134] After actuating the implant 2100 to the second
configuration, the release knob 1490 can be rotated in an opposite
direction as indicated by the arrow DD in FIG. 40 independent of
the housing 1485 and the actuation handle 1480. This causes the
intermediate shaft 1430 and the threaded portion 1442 of the
intermediate shaft 1430 to rotate in an opposite direction and in
turn causes the threaded portion 1442 of the distal end portion
1441 of the intermediate shaft 1430 to be decoupled from the
implant 2100. The implant insertion/removal tool 1400 can then be
removed from the body while leaving the implant 2100 behind in the
body of a patient.
[0135] The implant insertion/removal tool 1400 can remove and/or
reposition an implant already disposed within the body of a
patient. The insertion/removal tool 1400 can be inserted into the
patient's body and secured to the implant in the same manner as
described above. In some embodiments, a portion of the implant
and/or a portion of the insertion/removal tool 1400 can be
configured to facilitate the docking of the insertion/removal tool
1400 onto the implant. For example, in some embodiments, the outer
surface of the implant and/or a corresponding inner surface of the
insertion/removal tool 1400 can include a lead-in chamfer, a
tapered portion and/or a beveled edge to facilitate the docking of
the insertion tool onto the implant. After the insertion/removal
tool 1400 is secured to the implant, the insertion/removal tool
1400 can then be actuated to move the implant to the first
configuration (e.g., collapsed configuration). The implant can then
be moved to a new location within the patient's body or removed
form the patient's body.
[0136] FIGS. 42 and 43 illustrate an implant insertion/removal tool
2400, according to another embodiment. Implant insertion/removal
tool 2400 has a similar structure to and can operate in a similar
manner as the implant insertion/removal tool 1400. Implant
insertion/removal tool 2400 is configured to be used with an
implant 2200 configured to be inserted into an inetervertebral disc
space. FIG. 42 shows the implant 2200 in a first or collapsed
configuration and FIG. 43 shows the implant 2200 in a second or
expanded configuration. The implant 2200 is described in more
detail in U.S. patent application Attorney Docket No. KYPH-040/01US
305363-2277, which is incorporated herein by reference in its
entirety.
[0137] In some embodiments, the implant insertion/removal tool 2400
and the implant 2200 can be used to distract a disc space (not
shown) and/or define a void within a vertebra (not shown). In some
embodiments, the distal portion of the tool 2400 can be inserted
into a vertbra such that the implant 2200 is within the cancellous
bone portion of vertebra. The distal end portion of the tool 2400
can be inserted percutaneously via a pedicular approach. After the
implant 2200 is disposed within the vertebra, the tool 2400 can be
actuated, as described above such that the implant is moved from a
collapsed configuration to an expanded configuration. In this
manner, the tool 2400 and the implant 2200 can be used to define a
void within the cancellous bone. Moreover, in some embodiments, the
tool 2400 and the implant 2200 can be used repair a bone defect by
moving an endplate of the vertebra. In some embodiments, the tool
2400 can include a measurement device, such as that shown and
described above with reference to tool 1300, to provide the user
with an indication of the size change of the implant 2200.
[0138] FIGS. 44-54 illustrate an implant insertion/removal tool
3400, according to another embodiment of the invention. The
insertion/removal tool 3400 can be used to insert/remove and
actuate an implant between a first configuration (e.g., collapsed
configuration) and a second configuration (e.g., expanded
configuration). FIG. 44 shows the insertion/removal tool 3400
coupled to an implant 3100.
[0139] The implant 3100 is configured similar to and can function
in a similar manner as the implant 2100 described above. As shown
in FIGS. 46 and 47, the implant 3100 includes a tool engagement
member 3182 that includes a coupling protrusion 3185. The tool
coupling protrusion 3185 is configured to be removably coupled to
an insertion tool, such as insertion/removal tool 3400. The implant
3100 also includes a drive screw 3183 that has a tool head 3184.
The drive screw 3183 can be actuated to move the implant 3100
between a first configuration and a second configuration. The
coupling of the insertion/removal tool 3400 to the implant 3100 is
described in more detail below.
[0140] The implant insertion/removal tool 3400 (also referred to
herein as "insertion/removal tool") includes an outer shaft 3410,
an intermediate shaft 3430, an inner shaft 3450, an actuation
handle 3480, a housing 3485, a release knob 3490 and a support
handle 3495. The actuation handle 3480 is coupled to the inner
shaft 3450 and is configured to rotate the inner shaft 3450 about a
centerline of the actuation handle 3480 in a similar manner as
described above for insertion/removal tool 1400. The release knob
3490 is coupled to the intermediate shaft 3430 and is configured to
move the intermediate shaft 3430 proximally and distally as
described in more detail below. The support handle 3495 is offset
from the outer shaft 3410 and is used to stabilize the implant
insertion/removal tool 3400 during the insertion or removal of an
implant.
[0141] The outer shaft 3410 of the implant insertion/removal tool
3400 includes a proximal end portion 3411 and a distal end portion
3421 (see e.g., FIGS. 44 and 49). Outer shaft 3410 of the implant
insertion/removal tool 3400 also defines a lumen (not shown). The
intermediate shaft 3430 of the implant insertion/removal tool 3400
is configured to be disposed within the lumen defined by the outer
shaft 3410. The proximal end portion 3411 of the outer shaft 3410
is coupled to the housing 3485 and the release knob 3490. The
distal end portion 3421 of the outer shaft 3410 includes an implant
engagement portion 3422 configured to receive an external tool head
of an implant, such as the external tool head 3185 of the implant
3100 shown in FIGS. 46 and 47.
[0142] The intermediate shaft 3430 of the implant insertion/removal
tool 3400 includes a proximal end portion 3431 and a distal end
portion 3441 (see e.g., FIGS. 46, 48 and 50) and defines a lumen
3446 (see FIG. 46). The inner shaft 3450 of the implant
insertion/removal tool 3400 is configured to be disposed within the
lumen 3446 defined by the intermediate shaft 3430. The proximal end
portion 3431 of the intermediate shaft 3430 is coupled to the
release knob 3490 of the implant insertion/removal tool 3400. A
spring-loaded quick connect fitting 3442 is disposed within the
outer shaft 3410 at a distal end of the intermediate shaft 3430.
The spring-loaded quick connect fitting 3442 can be, for example, a
snap-ring or spring coil. The spring-loaded quick connect fitting
3442 can be compressed between an external tool head of an implant
and the distal end portion 3441 of the intermediate shaft 3430
[0143] For example, the tool coupling protrusion 3185 of the
implant 3100 includes a groove or detent 3190 configured to receive
the quick connect fitting 3442 of the insertion/removal tool 3400.
The intermediate shaft 3430 of the insertion/removal tool 3400 can
be moved proximally and distally to produce more or less
interference between the implant 3100 and the fitting 3442.
Actuation of the intermediate shaft 3430 by rotating the release
knob 3490 is described in more detail below. When the intermediate
shaft 3430 is moved distally such that more interference is
produced, the fitting 3443 produces a lock between the implant 3100
and the insertion/removal tool 3400. Retracting the intermediate
shaft 3430 (e.g., moving it proximally) allows the intermediate
shaft 3430 to detach from the implant 3100. For example, a user can
apply a slight pulling force on the insertion/removal tool 3400.
Thus, the fitting 3442 and the groove 3190 can collectively form an
interference fit such that both axial and rotational movement of
the implant 3100 relative to the insertion tool 3400 is limited or
prevented.
[0144] As shown in FIG. 50, the intermediate shaft 3430 includes a
coil portion 3436 that is bendable yet torsionally and
compressively stiff. The coil portion 3436 allows a compression
load to be applied to the fitting 3442 while being maneuverable
with the outer shaft 3410 and permitting rotation of the inner
shaft 3450 within the lumen 3446 of the intermediate shaft 3430.
The proximal end portion 3431 and the distal end portion 3441 can
be formed with, for example, cannulated tubing, which can be
attached to the coil portion 3436. The coil portion 3436 can be
various lengths of the intermediate shaft 3430. In some
embodiments, a coil portion is not included.
[0145] As shown in FIG. 49, a pin 3489 is attached to the proximal
end portion 3431 of the intermediate shaft 3430. The pin 3489 is
keyed into a slot 3492 of the release knob 3490 shown in FIG. 54.
During actuation of the intermediate shaft 3430, the pin 3489 rides
on a cam feature 3417 on the outer shaft 3410 shown in FIG. 51. The
cam feature 3417 drives the intermediate shaft 3430 proximally or
distally as the release knob 3490 is rotated allowing the
insertion/removal tool 3400 to release or lock onto an implant.
[0146] The inner shaft 3450 of the implant insertion/removal tool
3400 includes a proximal end portion 3451 and a distal end portion
3461 (see e.g., FIGS. 46, 48 and 52). The distal end portion 3461
of the inner shaft 3450 includes a drive member 3462 configured to
engage the tool head of the drive screw of an implant such as the
tool head 3184 of the drive screw 3183 of the implant 3100 shown in
FIGS. 46 and 47.
[0147] The proximal end portion 3451 of the inner shaft 3450 is
coupled to the actuation handle 3480 of the implant
insertion/removal tool 3400. The proximal end portion 3451 inner
shaft 3450 include a flange 3455 (shown in FIG. 52) configured to
be keyed into a slot 3479 of the actuation handle 3480 shown in
FIG. 51. A drive spring 3427 is also disposed within the slot 3479
of the handle 3480 and biases the inner shaft 3450 distally to
ensure the drive member 3462 fits tightly into the tool head of the
drive screw. Screws 3477 coupled to the handle 3480 are keyed into
the outer shaft 3410 to restrict axial movement of the handle 3480,
but allow rotational movement. Thus, the handle 3480 can be rotated
to actuate rotational movement of the inner shaft 3450.
[0148] As described above for implant insertion/removal tool 1400,
the implant insertion/removal tool 3400 can be coupled to an
implant and used to insert/remove the implant within a body of a
patient and can also be used to actuate the implant between a first
configuration and a second configuration. For example, the
insertion/removal tool 3400 can be used to percutaneously insert an
implant in a first configuration into a space between adjacent
spinous processes or within an intervertebral disc space.
[0149] To couple the insertion/removal tool 3400 to an implant,
such as the implant 3100, the driver member 3462 of the inner shaft
3450 is inserted through an opening 3181 of the tool engagement
portion 3182 of the implant 3100 such that the driver member 3462
engages the tool head 3483 of the drive screw 3484. As the driver
member 3462 is being inserted, the fitting 3442 can be moved into
the groove 3190 of the tool engagement portion 3182. The release
knob 3490 can be rotated to move the intermediate shaft 3420
distally to produce interference with the fitting 3442 and lock the
insertion/removal tool 3400 to the implant 3100. With the implant
3100 in a first configuration (e.g., collapsed), the implant 3100
can be inserted into a desired location within a patient's
body.
[0150] Once the implant is in place, the actuation handle 3480 can
be rotated as indicated by the arrow CC in FIG. 44. This in turn
rotates the inner shaft 3450 of the insertion/removal tool 3400 and
thus the drive member 3462 of the distal end portion 3461 of the
inner shaft 3450. Rotation of the drive member 3462 of the distal
end portion 3461 of the inner shaft 3450 in turn rotates the drive
screw 3184 of the implant 3100 and moves the implant 3100 to the
second configuration (not shown).
[0151] After the implant 3100 has been moved to the second
configuration (e.g., expanded configuration), the release knob 3490
can be rotated in an opposite direction as indicated by the arrow
DD in FIG. 44. This causes the intermediate shaft 3430 to translate
in a proximal direction. The translation releases the interference
between the intermediate shaft 3430 and quick connect fitting 3442
and allows the insertion/removal tool 3400 to be detached from the
implant 3100. The implant insertion/removal tool 3400 can then be
removed from the body while leaving the implant 3100 behind in the
body of the patient.
[0152] The implant insertion/removal tool 3400 can also be used to
remove and/or reposition an implant. The insertion/removal tool
3400 can be secured to an implant while the implant is still
disposed within the patient's body in the same manner as described
above. With the implant secured to the insertion/removal tool 3400,
the implant can be moved to its first configuration (e.g.,
collapsed configuration) by rotating the actuation handle 3480 of
the implant insertion/removal tool 3400 as indicated by the arrow
CC in FIG. 44. The implant, in its first configuration, can then be
removed and/or repositioned.
[0153] The various implants, insertion/removal tools, and dilation
devices described herein can be constructed with various
biocompatible materials such as, for example, titanium, titanium
alloyed, surgical steel, biocompatible metal alloys, stainless
steel, plastic, polyetheretherketone (PEEK), carbon fiber,
ultra-high molecular weight (UHMW) polyethylene, biocompatible
polymeric materials, etc. The material of one portion of a tool or
implant can be different than another portion.
[0154] While various embodiments of the invention have been
described above, it should be understood that they have been
presented by way of example only, and not limitation. Where methods
and steps described above indicate certain events occurring in
certain order, ordering of certain steps may be modified.
Additionally, certain of the steps may be performed concurrently in
a parallel process when possible, as well as performed sequentially
as described above. While specific embodiments have been described,
it will be understood that various changes in form and details may
be made.
[0155] Although the insertion/removal tools described herein were
described in connection with specific embodiments of spinal
implants, such as implants configured to be disposed within an
intervertebral disc space or in a space between adjacent
interspinous processes, and the insertion/removal tools can be used
with other types of implants having various configurations.
Moreover, although the insertion/removal tools (e.g., 1400, 2400,
3400) have been described as being used to insert and/or remove and
actuate and implant, the insertion/removal tools can also be used
to insert and actuate a dilation device (e.g., dilation head
3110).
[0156] In addition, although the dilation tools described herein
were described as having a particular embodiment of a dilation
head, other types of dilation heads can alternatively be
incorporated. For example, different embodiments of an expandable
dilation head can be configured to be inserted into a patient's
body and actuated using the actuation portion of the dilation tools
described herein. Likewise, the dilation head (e.g., 1310) can be
configured to be actuated using a different embodiment of an
actuation device. For example, the dilation head 1310 can be
configured to be coupled to, and actuated with, an
insertion/removal tool (e.g., 1400, 3400) as described herein. In
another example, the various spinal implants described herein can
also be configured to be actuated using an actuation portion as
described for dilation tool 1300.
[0157] Thus, although various embodiments have been described as
having particular features and/or combinations of components, other
embodiments are possible having a combination of any features
and/or components from any of the embodiments (e.g., dilation tool
1300, insertion/removal tools 1400, 2400, 3400) where appropriate.
For example, the various shafts of the insertion/removal tools can
include different types of coupling features to couple the
insertion/removal tool to an implant. In another example, the
driver member can have a variety of different shapes, sizes and
configurations configured to matingly engage a drive mechanism of
an implant not specifically described.
* * * * *